SilverBox SEC Filings

Polar Asset Management Partners Inc. reports beneficial ownership of 1,480,000 Class A ordinary shares of Silverbox Corp IV, representing 7.2% of the class. The filing is a Schedule 13G/A amendment and shows Polar holds sole voting and sole dispositive power over the shares.

The filing states Polar serves as investment adviser to Polar Multi-Strategy Master Fund and that the securities are held in the ordinary course of business and not for the purpose of changing or influencing control of the issuer. The disclosure provides clarity on a material passive stake above 5% in Silverbox Corp IV.

SilverBox Corp IV disclosed that AQR Capital Management, LLC, AQR Capital Management Holdings, LLC and AQR Arbitrage, LLC collectively beneficially own 1,347,002 Class A ordinary shares, equal to 6.59% of the class. The reporting parties state they possess shared voting and shared dispositive power over these shares and report no sole voting or sole dispositive power, indicating coordinated institutional ownership rather than unilateral control.

The filers certify the securities are held in the ordinary course of business and not for the purpose of changing or influencing control of the issuer. The disclosure therefore documents a material passive stake by a large investment adviser group without signaling an active governance or control intent.

SilverBox Corp IV is reported as being beneficially owned, in part, by The Goldman Sachs Group, Inc. and its subsidiary Goldman Sachs & Co. LLC. The filers disclose shared voting and dispositive power over 1,606,929 Class A ordinary shares, representing 7.9% of the class. The schedule is a joint filing by the parent and its broker/dealer subsidiary and includes an agreement authorizing joint amendments and an exhibit identifying the subsidiary that holds the reported position. The filers state the securities are held in the ordinary course of business and not for the purpose of changing control.

Healthcare of Ontario Pension Plan Trust Fund (HOOPP) reports beneficial ownership of 100,000 Class A ordinary shares of SilverBox Corp IV, representing 0.5% of the outstanding Class A shares based on 20,455,000 shares reported by the issuer. The position consists of 99,998 Class A shares plus 2 Class A shares held in units that include one-third of a redeemable warrant; whole warrants are exercisable at $11.50 per share. HOOPP states these securities are held in the ordinary course of business and were not acquired to influence control. HOOPP is a pension plan trust formed under Ontario law and reports sole voting and dispositive power over the 100,000 shares.

Barclays PLC reports beneficial ownership of 970,927 shares of SilverBox Corp IV common stock, representing 4.74% of the class. The filing states Barclays has sole voting and sole dispositive power over these shares, meaning it controls how the shares are voted and disposed. The schedule identifies Barclays Bank PLC as the subsidiary that acquired the securities and classifies the filer as a holding company. The filer certifies the shares were acquired and are held in the ordinary course of business and not to influence control of the issuer.

SilverBox Corp IV (SBXD) is a blank-check company that held $208,952,965 in a trust and reported total assets of $209,469,723 at June 30, 2025. The company generated $4.30 million of interest on trust investments for the six months and reported $3.39 million net income for the same period, while operating costs were $904,943 for six months. Cash outside the trust was $279,366 with working capital of $454,784, and Class A shares subject to redemption were recorded at a redemption value of $208,952,965.

The balance sheet shows material deferred obligations, including a $10.3 million deferred underwriting fee and $975,661 of deferred legal fees. Management disclosed substantial doubt about the company’s ability to continue as a going concern within one year absent additional financing. In subsequent events, on August 6, 2025 the company entered a business combination agreement with Parataxis and agreed to engage Santander US Capital Markets for advisory services with fees up to $10.3 million.

SilverBox Corp IV (NYSE:SBXD) filed an 8-K reporting a board transition effective June 25 2025.

Director Matthew Eilers resigned to avoid potential conflicts after joining an investment bank. The Board concurrently appointed Glenn Marino—a 30-year consumer-finance veteran and former Synchrony Financial CCO—as director and member of the Audit, Compensation, and Nominating & Governance committees.

• The Board designated Marino an “audit committee financial expert” under SEC rules.
• Standard indemnification executed; Marino is bound by the SPAC IPO letter to support the initial business combination.
• Eilers’ departure involved no disagreement regarding company policies.

No related-party transactions or family ties were disclosed.